Contents

Objectives

The Internet provides an indispensable means to exchange information over long distances. Connection to the Internet is enabled by following the implementation of the Open Systems Interconnection Reference Model (OSI model). In simple words, internet applications require a TCP/IP stack to pack and unpack information into data packets for proper transmission and reception over the Internet. The TCP/IP stack is usually implemented by software and included in the Operating System. Applications can use the stack transparently through socket programming.

Since a full-scale TCP/IP stack consumes a large amount of memory and processing power, a number of small footprint TCP/IP stacks have been devised for embedded systems, such as uIP and lwIP. Nevertheless, these TCP/IP stacks are usually not compatible to socket programming, and being implemented by software, still consumes a considerable amount of system resources. Therefore, hardware chips that implemented the TCP/IP stack (e.g. WIZNET W5300) emerged in recent years so as to offload the computation power from the host microcontroller unit (MCU).

This project aims to devise a driver and Linux socket wrapper inside freertos_posix for a hardware implemented TCP/IP stack. It is to be used in conjunction with a 8/16 bits embedded system such as (but not restricted to) the dsPic33F development board. Based on the Linux socket API, common application protocols (DHCP/HTTP/DNS/SMTP/SNMP/TELNET) are devised to enable remote control and monitoring.

Benefits

Provide a means to perform remote control and monitoring via Internet

Offload TCP/IP stack to chip, freeing memory and processing power of MCU to perform other tasks (e.g. HTTPS)

Socket API implementation allows more extensible framework for future development and upgrades